RU2551118C1 - Pulse voltage source - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: device containing a load, the first and second input terminals, the first and second output terminals, a switching transistor, an inductance, a discharge diode, a capacitor forming with inductance and inductance-capacitance filter of angle-shaped type, the resistive output voltage sensor, the unit of comparison of sensor voltage with voltage of the unit of reference voltage and the switching transistor control unit is also fitted with the unit of change of the current direction in a load. The unit is designed with a possibility of change of the current direction in a load.

EFFECT: expansion of functionality of the device at its implementation, obtaining output voltage with randomly pre-set periodic and continuous form, in particular, sinusoidal, with keeping of properties of simplicity of circuits of its implementation and rigid load characteristic.

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Description

The invention relates to electrical engineering and to pulsed power electronics, in particular to DC-to-AC converters - inverters and voltage regulators, and is intended for use in autonomous power supply systems and in electric drives of advanced aerospace aircraft with predominantly or fully electrified drive equipment.

A known method of pulsed DC voltage conversion (analogue), in which the energy of the metering double-winding inductor is increased at the stage of the closed state of the control key from the power source, and at the stage of its open state, this energy is partially or completely transferred to the load through the back-switched rectifier diode [Polikarpov A .G., Sergienko E.F. Single-ended voltage conversions in REA power supply devices. - M .: Radio and communications, 1989, p. 61, 67, 68].

The disadvantages of this method (analogue) are the reduced conversion efficiency due to significant losses in the double-winding inductor, since the conversion power is provided only by the pulsation of electromagnetic energy - this main component, and the conversion frequency, and a large voltage on an open control key that exceeds the supply voltage, with an additional switching surge due to the inductance of scattering of the metering inductor winding and a sharp surge of current into the additional diode, and that also the difficulty of providing a safe switching path for the transistor switch. This leads to the need to overestimate the installation power of the power switch and the metering choke to obtain the necessary reliability, which causes a deterioration in the energy, weight, size and economic performance of the converter.

A known method of pulsed DC voltage conversion and a device for its implementation (prototype) [Patent for the invention of the Russian Federation No. 2125334. Method of flyback pulsed DC voltage conversion. Kabelev B.V., Bull. 2 dated January 20, 1999].

The disadvantage of these known methods of pulsed DC voltage conversion and a device for its implementation are its narrow functional capabilities, namely the inability to obtain an output voltage with an arbitrarily set periodically-continuous form, in particular sinusoidal.

A known method of pulsed DC voltage conversion and a device for its implementation [Patent for the invention of the Russian Federation No. 2510871., Kabelev B.V., Bull. 2 dated January 20, 1999]. This pulsed DC-DC converter allows you to receive voltage on the load with an arbitrarily set periodically-continuous form, in particular sinusoidal.

The disadvantage of this method of pulsed DC voltage conversion and the device for its implementation is the requirement to use a primary voltage source with a midpoint, low load capacity (strong influence of the load resistance value on the output voltage value), the complexity of the key transistor control circuit (turned on by a half-bridge circuit) in the mode pulse-width modulation by a feedback signal from a voltage sensor at a load connected to the midpoint of the primary voltage source.

The closest in technical essence to the proposed and achieved effect (load capacity) is a pulsed voltage source (B.Yu. Semenov. Power electronics: from simple to complex. - M .: SOLON-Press, 2005. - 179 p.), Containing load, the first and second input terminals, as well as the first and second output terminals, a key transistor, inductance, a discharge diode, a capacitor forming an in-capacitive L-shaped filter with inductance, the output of which is connected to the first output terminal, to which it is also connected e the first output of the resistive output voltage sensor, the reference voltage unit, the unit for comparing the sensor voltage with the voltage of the reference voltage unit and the key transistor control unit, the first output of the key transistor connected to the first input terminal, the second output of the key transistor connected to the inductance terminal and the discharge cathode a diode, the anode of which is connected to the output of the capacitor, the second input terminal and the second output of the resistive output voltage sensor, the third output of which is connected to the first input of the unit for comparing the sensor voltage with the voltage of the reference voltage unit, the second input of the unit for comparing the sensor voltage with the voltage of the reference voltage unit is connected to the output of the reference voltage unit, and the output of the unit for comparing the sensor voltage with the voltage of the reference voltage unit is connected to the input of the key transistor control unit, and the output of the key transistor control unit is connected to the control input of the key transistor. This pulsed voltage source has a rigid load characteristic and a simple circuit for its implementation, but its drawback is its narrow functionality, namely the inability to obtain an output voltage with an arbitrarily set periodically-continuous shape, in particular sinusoidal.

The technical result of the invention is to expand the functionality of the device for its implementation, namely, to obtain an output voltage with an arbitrarily set periodically-continuous shape, in particular sinusoidal while maintaining the simplicity of its circuit implementation and hard load characteristics.

The specified technical result is ensured due to the fact that the known switching voltage source containing the load, the first and second input terminals, as well as the first and second output terminals, a key transistor, inductance, a discharge diode, a capacitor, forming an inductance-capacitive filter of an L-shaped filter type, the output of which is connected to the first output terminal, to which the first output of the resistive output voltage sensor, the reference voltage unit, the sensor voltage comparison unit are also connected with the voltage of the reference voltage unit and the control unit of the key transistor, while the first output of the key transistor is connected to the first input terminal, the second output of the key transistor is connected to the inductance terminal and the cathode of the discharge diode, the anode of which is connected to the output of the capacitor, the second input terminal and the second output of the resistive output voltage sensor, the third output of which is connected to the first input of the unit for comparing the sensor voltage with the voltage of the reference voltage unit, the second input of the comparison unit the voltage of the sensor with the voltage of the reference voltage unit is connected to the output of the reference voltage unit, the output of the unit for comparing the voltage of the sensor with the voltage of the reference voltage unit is connected to the input of the control unit of the key transistor, and the output of the control unit of the key transistor is connected to the control input of the key transistor, it is additionally equipped with a change unit the direction of the current in the load, while the first input of this block is connected to the second input and output terminals, the second input of this block is connected to the first th output terminal, and the first and second outputs of this block are connected to the load, while the block is configured to change the direction of the current in the load, and the pulsed voltage source is configured to create an arbitrary periodically-continuous voltage shape at its output and the possibility of synchronizing time instants a kink in the voltage curve with time instants of switching the direction of current in the load.

In the proposed pulsed voltage source, the possibility of creating an arbitrary periodically continuous form of voltage at the output thereof is provided by introducing into the feedback circuit from a separate external unit an external signal to control the shape of the output voltage of the pulse source. Moreover, since a switching voltage source is a system with automatic adjustment of the output voltage of a switching voltage source, it will process any signals of an external unit by increasing or decreasing the output voltage of a switching source so that the feedback voltage is always equal to the reference voltage. Moreover, if the external signal increases, the output voltage decreases and vice versa. This external signal can be of an arbitrary periodically continuous form, for example, the sine function module. In this embodiment, the output voltage of the pulsed source will be a unipolar voltage pulsating according to the law of an external signal, which in shape will reproduce the sine function module. To obtain a truly variable voltage by the sine function, it is necessary at certain times (when the output voltage of the pulsed source is close to zero) to force the current direction in the load to be reversed. When synchronizing the time points of the kink of the voltage curve with the time points of switching the direction of the current in the load, an alternating current will be obtained in it. The function of changing the direction of the current in the load is performed by the unit for changing the direction of the current in the load under the control of the synchronization signals of the external block of an arbitrary periodically-continuous form of the external signal. This unit is inserted into a pulsed voltage source.

Figure 1 shows a diagram of the proposed switching voltage source.

Figure 2 shows a diagram of a voltage generator sinusoidal shape.

Figure 3 shows a key management diagram of a unit for changing the direction of current in a load.

Figure 4 shows diagrams of changes in voltage and current circuits of figure 1.

The device of figure 1 contains a constant voltage source, made in the form of a rechargeable battery battery formed by a set of batteries B1-B6 connected in series. The battery of the battery has a positive pole 1 and a negative pole 2. The pulse voltage source has a first 3 and a second 4 input terminals, as well as a first 5 and a second 4 output terminals. The first input terminal 3 is connected to the positive terminal 1 of the battery. The second input and output terminals are interconnected, indicated in FIG. 1 as a common terminal 4 and connected to the negative terminal 2 of the battery.

The pulse voltage source 6 is equipped with a unit 7 for automatically adjusting the output voltage of the pulse voltage source 6. The input 8 of the pulse voltage source 6 is connected to terminal 4, the output 9 of the pulse voltage source is connected to terminal 5, and the input 10 of voltage regulation of the pulse voltage source is connected to output 11 of the block 7 automatic adjustment of the output voltage of the pulse source 6. The output 12 of the common wire of the source 6 is connected to the output 13 of the common wire of block 7, the output 14 of the common wire and the negative bottom pole 2 of the battery.

The pulse voltage source 6 contains a monolithic integrated circuit 15, for example, MAX724 or LM2596, a discharge diode VD1, a filter L1C1, and an output voltage sensor U _o , made in the form of a resistive divider formed by a constant resistor R2, a trimmer resistor R3, and a constant resistor R4. The integrated circuit 15 contains a composite bipolar key transistor VT1-VT2, a key control unit 16, made in the form of a pulse-width modulation pulse generating controller PWM, a conversion frequency generator 17, a reference voltage generator 18 U _ref and an error signal amplifier 19, the inverting input of which 20 connected to the slider of the tuned resistor R3 of the output voltage sensor U _o .

Block 21 changes the direction of the current in the primary winding W1 of the transformer T1 contains four field-effect transistors VT3-VT6, connected by a bridge circuit. The load in the form of a resistor R1 is connected in the diagonal of the bridge to points 22, 23, which are the outputs of block 21. In block 21 there is a circuit 24 for controlling transistors VT3-VT6. The gates of the VT3-VT6 field-effect transistors are connected to the outputs 25-28 of the feed to the gates of the control signals of the VT3-VT6 transistors. The input 29 of block 24 is used to synchronize the switching process of transistors VT3-VT6, the signals from the output 30 of block 7 to the input 31 of block 21 and then to the input 32 of block 24.

The bridge from transistors VT3-VT6 is powered by a battery and a pulse source 6, while the sources of transistors VT4, VT6 are connected to a common terminal 14 and pole 2 of the battery through input 33 of block 21, the drains of transistors VT3, VT5 are connected to terminal 5 and terminal 9 the output voltage U _{o of the} pulse source 6 through the input 34 of the block 21.

The input 29 of the circuit 24 through the input 35 of the block 21 from the output 11 of the block 7 sends the control signals of the transistors of transistors VT3-VT6.

The anodes of the diodes VD2, VD3 are connected respectively to the outputs 22, 23 of the block 21, and the cathodes of the diodes VD2, VD3 are connected by the output 36 and further to terminal 3 and the positive pole 1 of the battery.

Block 7 of the automatic adjustment of the output voltage of the pulse source 6 is made in the form of a function generator of the sinusoidal voltage module (GOS), the output 11 of which is connected through the resistive divider R2-R4 to the voltage regulation input 10 of the pulse source 6. Output 13 of block 7 with the common wire 12 of voltage source 6 .

The block diagram of the seeker is shown in figure 2. The sinusoidal voltage generator (GOS) of block 7 is made on microprocessor D1 and digital-to-analog converter D2. The function of the sinusoidal voltage module in digital form is generated using the microprocessor software, and the digital-to-analog converter D2 is transmitted through the digital channel A of the microprocessor D1, the output of which forms an analog form of the function of the sinusoidal voltage module as shown in diagram a) of Fig. 2. At the same time, microprocessor D1 programmatically generates clock pulses and, through channel B, sends them to the output 30 of block 7. The leading edges of these clock pulses coincide with the break points on the curves of the function of the modulus of the sinusoidal voltage.

The control circuit 24 of transistors VT3-VT6 of block 21 is shown in Fig. 3 and contains a differentiating circuit consisting of a capacitor C3, an operational amplifier D3 with a feedback resistor R10, a diode VD4, a D-trigger DDI and two half-bridge drivers DD2, DD3 of the upper and lower arms .

Diagrams a), b), c), d), e) of Fig. 3 show the pulse shapes at the points of the circuit indicated by arrows.

In the diagram of Fig. 4: T is the pulse repetition period of the sinusoidal voltage, U ₁₁ is the voltage at the output 11 of the sinusoidal voltage generator of the GSN unit 7 (output 11 of the unit 7), U ₉ is the voltage at the output 9 of the pulse voltage source 6, U _ar - voltage feedback at the input 20 of the integrated circuit 15, U ₃₀ - synchronization voltage at the output 30 of block 7, U _VT6 - voltage at the gates of transistors VT3, VT6, U _VT4 - voltage at the gates of transistors VT4, VT5, U _VD2 - voltage at the anode VD2, U _VD3 - voltage at the anode VD3, U _R1 - voltage at the resistor R1, performing consumer active load functions.

The device operates as follows.

First, we consider briefly the standard process of operating a pulse voltage source 6 in the absence of signals from block 7. (see, for example, B. Yu. Semenov. Power electronics: from simple to complex. - M.: SOLON-Press, 2005. - 179 s. .).

When applying voltage U _in from the battery of the battery to the inputs 4 and 8, the master oscillator 17 generates voltage pulses of a sawtooth shape with a frequency of, for example, 100 kHz (period of 10 μs). The feedback signal, taken in the form of voltage U _arr , from the output voltage sensor U _o , made in the form of a resistive divider R2, R3, R4, is fed to the inverting input of the error signal amplifier 19 and is compared with the reference voltage of the reference voltage generator 18 U _ref . The key transistor control unit 16 generates rectangular pulse-width modulation pulses PWM from the sawtooth signal of the generator 17 and transfers them to output 22, by which the composite bipolar key transistor VT1-VT2 opens for a period of time t ₀ . The duration t _{0 of} these rectangular pulses depends on the ratio of the voltages U _ref and U _arr . If U _{ref is} greater than U _arr , then the amplifier 19 at the input 23 of block 16 generates a signal to turn on the composite bipolar key transistor VT1-VT2. As soon as U _ref becomes less than or equal to U _arr , the amplifier 19 at the input 23 of block 16 generates a signal to turn off the composite bipolar key transistor VT1-VT2. During time t ₀ (when the composite bipolar key transistor VT1-VT2 is open), the capacitor C1 is charged through the inductance L1. The output voltage U _o and the voltage U _arr feedback increase. The value of U _arr associated with the value of U _{o the} ratio:

where φ and n are, respectively, the rotation angle and the number of full revolutions of the slider of the tuning resistor R3.

As soon as the value of U _arr is equal to or greater than the reference voltage U _{ref of} block 18, the amplifier 19 at the input 23 of block 16 generates the closing signal of the composite bipolar key transistor VT1-VT2. In this case, the inductance L1 through the discharge diode VD2 gives the stored energy to the capacitor C1, and the latter, when the key transistor VT1-VT2 is closed, is discharged to the load R1. The output voltage U _o and the voltage U _ar feedback are reduced. As soon as the value of U _arr is less than the reference voltage U _{ref of} block 18, the amplifier 19 at the input 23 of block 16 generates a signal to open the composite bipolar key transistor VT1-VT2. The capacitor C1 is charged through the inductance L1, the operation of the pulse voltage source 6 in the absence of signals from block 7 is repeated many times according to the procedure described above. In this mode of operation, the pulse voltage source 6 in the absence of signals from block 7 performs the functions of an automatic voltage stabilizer U _o with any changes in the voltage U _in from the battery of the battery at inputs 4 and 8. This is a generally accepted, standard mode of automatic voltage regulation of the U _o pulse voltage source 6 in the absence of external signals from block 7.

To solve the technical problem posed in the present invention, a pulse voltage source 6 is used in the automatic adjustment of the voltage U _out under the influence of external signals from block 7.

The impulses of the sinusoidal voltage, in the form reproducing the modulus of the sine function and generated at the output of the GOS generator (see figure 2.), are highlighted at the output 11 of block 7 and have the form shown in figure 4, a graph of U ₁₁ (t).

The dependence of U ₁₁ (t) during each period T can be represented as:

where T is the period of the sine wave, sec.

This voltage is the sum of the voltage across the resistors R3-R4 of the resistive divider R2-R4, and the voltage U _ar feedback will then be equal to:

where U ₀ is the voltage across resistor R4 at time t = 0.

Using the trimmer resistor R11, the value of U _{0 is} set equal to U _ref . In this case, during the operation of the pulse voltage source 6 at time t = 0, U _{arr is} greater than or equal to U _{ref of} block 18. The amplifier 19 at the input 23 of block 16 generates a close signal for the composite bipolar key transistor VT1-VT2. The value of the voltage U _o is equal to close to zero, because the value of U _{arr is} formed due to the external voltage U ₁₁ (t), which is equal to t = 0 U ₀ , i.e. U _ref . Over time t, the value of U ₁₁ (t) decreases. U _arr also decreases, and the pulse voltage source circuit 6 monitors this decrease in _arr by periodically tearing off the composite bipolar key transistor VT1-VT2, thus increasing the voltage U _out until U _arr is equal to U _ref at U ₁₁ ( t) at the current time t. Since U ₁₁ (t) decreases during the first half of the period T, the voltage U _o will increase in sinus during the first half of the period T, during the second half of the period T U ₁₁ (t) the sinus increases while the voltage U _o will be sinus decrease during the second half of period T.

During the period T, the voltage U _{o out} of phase will repeat the voltage U ₁₁ (t) of block 7, which in shape reproduces the sine function module (see figure 4, graph U ₉ ). Moreover, U _arr during time t does not change in magnitude, because its changes are compensated by automatically monitoring the changes U _arr by the pulse voltage source circuit 6 when the voltage U ₁₁ (t) changes in block 7 (see Fig. 4, graph U ₂₀ ).

From the output 9 of the pulse voltage source 6, the voltage U _o , which reproduces the sine function module in form, passes through terminal 5 and input 34 of block 21 to the drains of transistors VT3, VT4.

To form a sinusoid in load R1, circuit 24 implements each, for example, an even period of voltage U _o , changing the direction of the current in load R1.

To this end, from the output 11 of block 7, the voltage U ₁₁ (t) is supplied to the input 29 of the circuit 24. Simultaneously, from the output 30 of the block 7, the synchronization pulses arrive at the input 32 of the synchronization circuit 24 of the block 21. The differentiating chain, consisting of a capacitor C3, a feedback operational amplifier D3, and a feedback resistor R10 and a diode VD4, selects from the pulses arriving at the input 29 of the circuit 24 only the edges of the kink function of the sine wave module and transfers them to the information input D of the D-trigger located in the counting mode. If there is a counting pulse at the counting input C of the D-flip-flop coming from the output 30 of block 7, the D-flip-flop switches from one state to another, for example, from a state with a high voltage level at the output Q and a low voltage level at the inverting output Q of the D-flip-flop to a state with a low voltage level at the output Q and a high voltage level at the inverting output Q.

Upon receipt of the following pulses at the inputs D and C, the state of the D-trigger will change to the opposite. The duration of the pulses at the output Q and the inverting output Q of the D-trigger is equal to the period T of the pulses of the sine function module (see Fig. 4, graph U ₉ ) at the output 11 of block 7 (see Fig. 4, graph U ₁₁ ). The leading and trailing edges of these pulses coincide with the moments of kinks in the output voltage curve U _o at output 9 of source 6 (see Fig. 4, graphs U _VT4 and U _VT6 ). These pulses through the drivers DD3 and DD4 from the outputs 25, 26, 27. 28 are supplied respectively to the gates of the transistors VT3, VT4, VT5, VT6, alternately including pairs of transistors VT3, VT6 or VT4, VT5, see figure 4, graphs U _VT6 and U _VT4 . In this case, the voltage shape at the anodes of the diodes VD2, VD3 will correspond to the voltage shape at the output 9 of the pulse voltage source 6 (on VD2 there are odd half-waves of voltage, and VD3 is even half-waves of voltage U _o ), and the current in load R1 will have a sinusoidal shape. The voltage waveform across the resistor R1 is shown in FIG. 4, a graph of U _R1 (t).

If the load R1 is purely inductive, then at the moments of switching the pairs of transistors VT3, VT4 or VT5, VT6, voltage and current surges will appear on the anodes of the diodes VD2, VD3 due to the EMF of the inductance R1, which open the diode when the transistors VT3 or VT5 close VD2 or VD3. through which at these moments the battery of the battery is charged (energy recovery).

The most effectively proposed device operates at φ = 0. In this case, there are no restrictions on the shape of the voltage U _o (see Fig. 4, graph U ₉ ).

Information sources

1. B.Yu. Semenov. Power electronics: from simple to complex. - M.: SOLON-Press, 2005 .-- 179 p.

Claims (1)

A switching voltage source containing a load, the first and second input terminals, as well as the first and second output terminals, a key transistor, inductance, a discharge diode, a capacitor forming an in-capacitive L-shaped filter with inductance, the output of which is connected to the first output terminal to which is also connected the first output of the resistive output voltage sensor, the reference voltage unit, the unit for comparing the sensor voltage with the voltage of the reference voltage unit and the key transistor control unit wherein the first terminal of the key transistor is connected to the first input terminal, the second terminal of the key transistor is connected to the inductance terminal and the cathode of the discharge diode, the anode of which is connected to the terminal of the capacitor, the second input terminal and the second terminal of the resistive output voltage sensor, the third terminal of which is connected to the first the input of the unit for comparing the voltage of the sensor with the voltage of the unit of the reference voltage, the second input of the unit for comparing the voltage of the sensor with the voltage of the unit of the reference voltage is connected to the output b reference voltage, and the output of the unit for comparing the voltage of the sensor with the voltage of the unit of the reference voltage is connected to the input of the control unit of the key transistor, and the output of the control unit of the key transistor is connected to the control input of the key transistor, characterized in that it is additionally equipped with a unit for changing the direction of the current in the load, the first input of this block is connected to the second input and output terminals, the second input of this block is connected by the first output terminal, and the first and second outputs of this block connected to the load, while the unit is configured to change the direction of the current in the load, and the pulsed voltage source is configured to create an arbitrary periodically continuous form of voltage at its output and the ability to synchronize the time points of the kink of the voltage curve with the time switch the direction of current in the load .

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